Valve insert



FIG. 1 is a front perspective view of a valve insert showing my newdesign;

FIG. 2 is a rear perspective view thereof;

FIG. 3 is a right side elevational view thereof;

FIG. 4 is a left side elevational view thereof;

FIG. 5 is a top plan view thereof; and,

FIG. 6 is bottom plan view thereof.

CLAIM The ornamental design for a valve insert, as shown and described.